Grinding machine



v2 Sheets-Sheetl 1 Nov. 12, 1940. H. s.A INDGE GRINDING' MACHINE Filed June 15, 1940 IDN n w u Tm .--Vim Imm E MND v .l Uw., A llllllllllllllwmll nl@ WWII IIHH Hllilll. ,H H HH JK HERBERT .SII/V055 NOV'. 12, 1940. H. |NDGE y 2,221,638

GBINDING MACHINE I Filed June 15, 1940 2 Sheets-Sheet 2 :www

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Patented Nov. 12, 1940 UNITED STATES PATENT OFFICE GmNnlNG MACHINE tion of Massachusetts Application June 15, 1940, serial No. 340,761 s claims. `(c1. 5192) The invention relates to grinding machines, and more particularly to agrinding machine for grinding plane surfaces and the like.

One object of the invention is to provide a simple and thoroughly practical grinding machine. .A further object of the-invention is to provide a balanced grinding machine wheel slide construction. Another object of the invention lis to provide a grinding wheel slide construction in which the wheel slide is at`all times maintained in a substantially balanced condition.

Another object of the invention is to provide a vertically movable slide to support a Wheel slide in such a manner thatthe weight of the l5 Wheel slide is counterbalancedv Another object of the invention is to provide a motor driven grinding Wheel on a wheel slide in which the Wheel slide is moved transversely and the motor together with its mounting is moved transverseg() ly on the Wheel slide in the opposite direction Hautomatically to counterbalance the weight of the slide and wheel during transverseA adjustment thereof. Other objects will be in part obvious or in part pointed out hereinafter.

2,-, 'I'he invention accordingly Aconsists in the feav tures of construction,.combinations of elements,

and arrangements of parts, as will be exemplified in the structure to behereinafter described, and the scope of the application of which will y, be indicated in the following claims.

vIn the accompanying drawings, in which is shown one of various possible embodiments of the meclranical features of this invention, FigiL l is an end elevation of a grinding'ma- 7, chineembodying the invention;

g Fig. 2 is a fragmentary perspectiveview, partly in section, showing the details of the wheel slide construction;

, .FigI 3 is a fragmentary longitudinal sectional m view through the grinding )wheel spindle and the wheel slide traversing mechanism;

Fig. 4 is a fragmentary detail view of the traversing mechanism for the grinding wheel slide; and

45 Fig. 5 is a fragmentary cross-sectional view, on an enlarged scale, taken approximately on the line 5-5 of Fig. 3 through the wheel spindle.

As illustratedin the drawings, a surface grinding `machine has been shown comprising -a base4 I Il which supports a 'longitudinally reciprocable work supporting table II on a V-way I2 and a at way I3.

Ther table IImay be traversed longitudinally 'either manually or by power. For the sake o f 55 illustration, a manually operable `traversingr vmechanism has been' illustrated comprising a.

hand Wheel I which is supported on a shaft I6. The shaft I6 supports a gear I1 which meshes with a gear I8. The gear I8 is suppbrted ona rotatable shaft I9 which carries a gear 5 20. The gear vmeshes with a rack bar 2I which is xedly mounted on'the under side of the table I I. It will be readily apparent from the foregoing disclosure that a. rotary motion of the hand wheel I5l will be transmitted through 10 the gear mechanism above described to traverse the table II longitudinally. The direction o f movement of the table I I is dependent upon the v direction of rotation of the manually operablev traverse Wheel I5. 15 A vertically extending column is xedly mounted on the rear portion of the base I0. The column 25 is provided with a substantially 1 shaped slideway 26 which serves as a support4 for a vertically movable slide 21. The slide 21 is ar- 20 ranged so that it `may be moved vertically by means of a feeding mechanism comprising a nut .28 which is formed integral with or xedly mounted to the slide 21.

A ufeed screw 29 is rotatably supported in bearings 30 and 3I and the g5 screw meshes with or engages the nut 28. The bearings 30 and 3| are arranged to permit rotary motion thereof but to prevent endwise movement of the screw I9. A beyel gear 32 is mounted on the lower end of the feed screw 28 and 30 meshes 'with a bevel gear 33 which is mounted on the left-hand end ofa rotatable shaft 34.

, The right-hand end of the shaft 34 (Fig. 2)

is provided with a gear 3 5 which meshes with a gear 36 carried on the inner end of la rotata- 35 bleshaft 31. A manually operable hand wheel 38 is lmounted on the outer end of the .shaft 36 by means of which thervertical adjustment of the slide 21 may beV readilyeifected when`desired. It will be readily apparent from the foregoing disclosure that a rotary motion of the hand wheel 38 will be transmitted through the gear 36, the gear 35,- the shaft 34, the bevel gear 33,

the bevel gear 3,2, to rotate the feed screw 29 and thereby transmit a vertical movement to the slide 21. The direction of movement of the hand wheel'38 determines the direction of movement of the vertical slide, that is, Whether it moves up or down.

.'Inor'der to provide-a freely movable mounting 50 for the vertical slide 21, it is desirable to counterbalanceth'e weight carried thereby so that the slide will not cramp as 4the feed screw 29 is rotated to raise or lower the same. In order j to counterbalance the slide 21 in one direction, 55

-way formed on a a pair of rearwardly extending plates and 4| are provided which are preferably either flxedly mounted to the slide 21 or formed integral therewith. As illustrated in the drawings, the plates 48 and 4| are arranged on opposite sides of the column 25. At the rear end of each of the plates 40 and 4|, enlarged members 42 and 43 are provided which are ofy suflicient size to counter-balance the weight of a wheel slide and its support to be hereinafter described, thus counterbalancing the weight of the slide in a direction normal to the axis of the grinding wheel.

A transversely extending slideway 45 is fixedly mounted on the vertical slide 21. The slideway 45 serves as a support for a transversely movable grinding wheel slide 46 which is provided with ways which mate with the ways 45. VThe wheel slide 46 serves as a support for a rotatable Wheel spindle 41 which in turn supports a rotatable grinding wheel 48. The lwheel spindle 41 is provided with an enlarged cylindrical portion 5| which is journalled within the bearings 49 and 50 on the Wheel slide 46. The enlarged portion 5| of the wheel spindle 41 is provided with a central longitudinally extending aperture 52 which is of a non-circular shape preferably a trilobe shape (Fig. 5); such as that shown in the prior U. S. patent to .Everard Stubbs, No.-

1,912,412 dated June 6, 1933, to which reference may be had for details of disclosure not contained herein.

In order to maintain the Wheel slide 46 .in a balanced condition to facilitate free vertical movement of the slide 21, it is desirable to providev an automatically operated'mechanism to counterbalance the wheel slide 46 during its transverse movement. As 'illustrated in the drawings, a

longitudinally extending dovetailed way 55 is' formed on the Wheel slide 46. The dovetailed slideway 55 mates with a correspondingly shaped slide 56 which in turn serves as a support for an electric motor 51. The motor 51 is provided with an armature shaft 58 which is fxedly connected to a tri-lobe shaft 59 which mates with the aperture 52 (Figs. 3 and 5) formed within the enlarged portion 5| of the wheel spindle 41. The tri-lobe shaft 59 and the aperture 52 provide a telescopic driving connection between the motor 51 and the Wheel spindle 41 so that the motor 51 together with its supporting slide`56 may be adjusted along the dovetailed slideways 55 to counterbalance the weight of the wheel end of the wheel slide 46 shaft 69. The spiral gear during its transverse movement alongv the slide- A manually operable traversing mechanism is provided for traversing the Wheel slide 46 trans- -versely relative tothe base I0 to position or index the grinding Wheel 48 in grinding a plane surface of greater width than the operative face of the grinding wheel 48. This traversing mechanism may comprise a manually operable rotatable traversing wheel 65 which is mounted on the outer end of a rotatable shaft 66. The shaft 66 is journalled in suitable bearings (not shown) supported 'inthe wheel slide 46. The shaft 66 supports a spiralgear 61 which meshes with a spiral gear 68 which is supported on arotatable 681meshes with a spiral rack bar'10 which is xedly mounted o-n the slideway member 45. It will be readily apparent from the foregoing disclosure that a rotary motion ol the manually operable hand wheel 65 will be transmitted through the shaft 66, the spiral gear,

61, the spiral gear 68, to produce a transverse movement of the wheel slide 46. 'The direction of rotation of the hand wheel 65 will determine the direction of movement of the wheel slide 46 and the grinding Wheel 48.

In order to automatically maintain the wheel slide 46 in balance during its transverse indexing movement, it is desirable to provide a mechanism for automatically moving the slide 56 and the motor 51 relative to the wheel slide 46 in a direction opposite to the indexing movement of the slide 46 so that the weight of the motor 51 and its supporting slide 56 will at all times counterbalance the weight of the grinding wheel 48 and its supporting spindle and mounting. This is preferably accomplished by providing a mechanism which operates by and in timed relation with the Wheel slide traversing mechanism. In the preferred form, the lgear 68 is slidably keyed to the shaft 68. The gear 68 is arranged for a rotary motion but is held against longitudinal motion by thrust surfaces formed within the wheel slide 46. The shaft 69 is provided with a screw threaded portion 1| which meshes with or engages a nut 12 which is fixedly mounted within the motor supporting slide 56. The pitch of the screw 1| and the direction of the lead thereof is such that the motor supporting slide 56 together with the motor 51 moves' at a desired and predetermined rate in the opposite direction to the movement of the wheel slide 46 so as to maintain the wheel slide 46 in substantial balance during its transverse feeding or indexing movement, thus facilitating vertical movement or adjustment of the slide 21.

The operation of this grinding machine will be readily apparent from the foregoing disclosure. A work piece 80 is mounted on the work supporting table ||,.the vertical slide 21 is moved downwardly by rotation of the hand wheel 38 to bring the peripheral surface of the wheel 48 into engagement with the surface of the Work, and the grinding operation proceeds during the traversing or reciprocating movement of the table At one or both ends of the longitudinal movement of the table Il, the wheel slide 46 is indexed transversely by an amount equal to or less than the width of the operative face of the grinding wheel. During this transverse adjusting movement as produced by a rotary motion of the manually operable traversewheel 65, a rotary motion is imparted to the screw 1| to move the motor supporting slide 56 and the driving motor 51 in a direction opposite to they direction of movement of .the wheel slide so tha; the weight of the slide 56 and the motor 51 will at all times substantially counterbalance the weight of the grinding wheel y 48 and its supporting spindle 41 so that the entire wheel slide assembly is maintained in substantial balance, thus facilitating free movement of the vertical slide 21 without clamping.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and tween said motor and said grinding wheel, a`

movable slide on said wheel slide to supportsaid motor, a traversing mechanism to move said Wheel slide, and means automatically to move said motor and its supporting slide relative to the wheel slide to maintain said wheel slide in balance. g

2. In a grindingv machine having a base and a movable work table, a movable wheel slide on said base, a rotatable grinding wheel on said slide, an electric motor, driving connections between said motor and said' grinding wheel, a movable slide on said wheel slide-to. Support said motor, a traversing mechanism to move said wheel slide, and means actuated by and in timed relation with said traversing, mechanism automatically to movesaid motor and its supporting slide relative to and in a direction opposite to the movement of the wheel slide to maintain the wheel slide in balance.

3. Ina grinding machine having a base and a longitudinally reciprocable work table, a transversely movable wheel slide thereon, a rotatable grinding wheel on said slide, an electric motor,

driving connections between said motor and said grinding Wheel, a traversing mechanism to move said slide, a movable slide on said wheel slide to support said motor, and means actuated by and in timed relation with said traversing mechanism automatically to move saidmotor and its supporting slide relative to the wheel slide to maintain said wheel slide in balance.

4. In a grinding machine having a base and a longitudinally reciprocable work table, a transversely movable slide thereon, a rotatable grinding wheel on said slide, an electric-motor, telescopic driving connections between said motor and grinding wheel, a traversing mechanism to move said slide, a longitudinally movable slide means actuated by and in timed relation with said traversing mechanism automatically to move said motor and its supporting slide in a direction opposite to the transverse movement of the slide relative to the wheel slide to maintain the wheely slide in balance.

5. In a grinding machine having a base and a longitudinally recoprocable work table, a transversely movable slide thereon, a'rotatable grinding wheel on said slide, an electric motor, tele-v scopic driving connections between said motor and said grinding wheel, a traversing mechanism including a manually operable gear and rack mechanism to move said slide, a longitudinally movable slide on'said wheel slide to support said motor, and means including a nut and screw mechanism actuated by and in timed relation with said gear mechanismautomatically to move said motor and its supporting slide relative t'o the wheel slide toK maintain `said wheel slide in `balance.

motor, and means including a nut and screw mechanism actuated by and in timed relatio HERBERT s. INbGE.

on the wheel slide to support said motor, and 

